The present invention relates to a system for automatically identifying the mold source of a bottle and providing a running history of the identity and status of an entire procession of bottles.
It is known in the art to automatically identify the contents or source of production of a container by a variety of surface markings placed on the exterior thereof. For example, nonreflective stripes may be placed on the exterior of a metal can to connote the contents of the can, as described in U.S. Pat. No. 2,647,799. A plurality of optical source-detector pairs is used to identify the markings on the can to provide an indication of its contents. Also, it is known to inspect a transparent bottle by forming projections on the bottom of the bottle as described in U.S. Pat. No. 3,301,396. The projections are counted by a plurality of mechanical sensing arms. The total number of projections identifies the mold source of the bottle.
Such identification systems are unduly time-consuming and require a multiplicity of inspection equipment. The disadvantages of such systems are dicussed in greater detail in application Ser. No. 467,702 entitled "Method And Apparatus For Identifying A Bottle" filed May 6, 1974 assigned to the assignee herein and incorporated herein by reference. In application Ser. No. 467,702, there is described a method and apparatus for identifying a transparent bottle provided with one or more sectors spanning a circumferential zone with prism-like timing marks thereon using a laser beam and sensor. The sensor generates a series of digital pulses in response to the passage of the laser beam through the timing marks. The inspection technique is simple, fast and reliable and requires a minimal amount of inspection equipment. Only a single inspection station is required to identify each bottle in an entire procession. The mold source of the bottle is rapidly identified by a hard-wired electronic control circuit described in the application. The circuit automatically computes the mold number of a bottle and compares the computed mold number with predetermined mold numbers corresponding to molds known to be producing defective bottles. The circuit activates an ejector mechanism for ejecting the bottle under inspection when the computed mold number matches any of the stored mold numbers.
A hard-wired control system is relatively expensive and inflexible compared to a programmable computer control system for the same purpose, see Callin and Baskin, Microcompressor System Design, Digital Design (February 1975), Hernandez, Mini/Micro I/O Interfaces, Digital Design (April 1975), and Davidoro, Microcomputers--What They Mean to Your Company, Intel Application Note (1975). Thus, the number of logical functions which can be performed by the hard-wired circuit is inherently limited whereas the programmable computer control system offers increased system capability. For example, in the hard-wired circuit disclosed in application Ser. No. 467,702, the computed mold number for each bottle cannot be stored for later use. As a result, it is not possible to provide a history of the identity and status of more than one inspected bottle at a time. Stated otherwise, the information output and control capacity of the hard-wired circuit is relatively limited. Moreover, any modification to a programmable computer control can be effected simply and quickly by modifying existing programs whereas modification of hard-wired systems is more cumbersome and slow.